Lag Ba’omer is a day of vivid memories for me. It was the only day that my primary school in London would go on an outing, full of packed lunches and adventures, to celebrate and learn about the Bar Kochba uprising. We would shoot toy bows and arrows and generally have a good time.

As I grew older I learned about other themes of the day. The death of the 24,000 students of Rabbi Akiva, who were the...